<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>初始化 state - 紫霞仙子</title>
</head>
<body>
    <div id="root"> </div>

    <script src="../js/react.development.js"></script>
    <script src="../js/react-dom.development.js"></script>
    <script src="../js/babel.min.js"></script>

    <script type="text/babel">
        //数据
        // let data = {
        //     isNight: true
        // }

        //创建虚拟 DOM
        class App extends React.Component{
            //构造方法
            //state 属性声明方式一
            // constructor(){
            //     super();
            //     //添加组件实例对象属性 state
            //     this.state = {
            //         isNight: false
            //     }
            // }
            
            //state 属性声明 方式二
            state = {
                isNight: true
            }

            render(){
                //render 方法中 this 是指向实例对象的
                return <div>
                        <h2>至尊宝, 我是{this.state.isNight ? '青霞仙子' : '紫霞仙子'}</h2>    
                    </div>
            }
        }

        //渲染
        ReactDOM.render(<App />, document.querySelector("#root"));


    </script>
</body>
</html>